Developing and utilizing computational physics approaches to study biology problems
Developing and utilizing computational physics approaches to study biology problems
Anti-mitotic drugs are highly desirable chemotherapy drugs for cancer treatment. Traditional anti-mitotic drugs destroy microtubule dynamics by depolymerizing or stabilizing microtubules, which blocks the mitosis and then kills the overactive cancer cells. Even though these anti-mitotic drugs have achieved great success in chemotherapy for cancer treatment, they face significant issues including serious side effects and strong drug resistance for some types of cancers. While microtubules provide the scaffold for mitosis, it is the interaction of kinesins with microtubule that is responsible for mitotic separation. Human kinesin-5s (Eg5) thus present ideal alternative anti-mitotic drug targets, especially for cancers that are resistant to microtubule targeting drugs. Understanding the fundamental mechanisms of Eg5 is highly demanded. Using computational physics approaches, we systematically studied the interaction between Eg5 and the microtubule. The electrostatic features indicate that the charge distribution on the motor domains of Eg5 provides complicated interactions to the microtubule. The analyses on hydrogen bonds and salt bridges demonstrate that on the binding interfaces of Eg5 and tubulin heterodimer, the salt bridge plays the most significant role in holding the complex structure. Compared with the salt bridges between Eg5 and α-tubulin interfaces, the salt bridges between Eg5 and β-tubulin have a greater number and higher occupancies. This asymmetric salt bridge distribution may play a significant role in Eg5’s directionality. The residues involved in hydrogen bonds and salt bridges are identified in this work, which may be helpful for anticancer drug design.